ENEM20003: Thermofluids Engineering Applications
Title: Assessments of Energy Performance and Thermal Comfort of the Non-residential Building
The development of strategies for efficient and effective energy management in buildings is essential not only for reducing the cost of energy but also to save the environment. Effective HVAC control strategies should be developed for improved thermal energy management. Energy savings of up to 30% or even more can be achieved through introducing proper energy conservation measures (ECM) in existing building without compromising the indoor comfort. The speed and reliability of today’s computers and the availability of suitable energy simulation software with optimization techniques have given us the opportunity to take advantage of thermal design of buildings and to make decision for energy conservation purposes.
According to Commercial Buildings Energy Code, about 65% of electrical energy is used for space conditioning in Australia. Rockhampton is a hot and humid area and Australian Bureau of Meteorology records show that in 2005 Rockhampton had the hottest temperature in this region in 37 years. This clearly indicates that the HVAC system of a building in this region has a huge potential for energy savings. Development of strategies for an efficient energy management is thus very important.
In this project, the student teams should aim to study energy management strategies for existing heating, ventilating and air conditioning (HVAC) systems of a reference building in Rockhampton, Queensland, Australia. The details of the building will be provided on the Moodle page. There are many factors to be considered when considering a HVAC system for a building or industry.
Some of these factors are:
• The comfortable conditions (temperature, humidity, air velocity, air quality, etc.)
• The installation method, operating procedure and maintenance
• The cooling and/or heating loads in each zone of the buildings or industry
• The method of controlling the system to ensure comfortable conditions maintained throughout
• The identification of energy conservation opportunities through better design, modifications, retrofitting, etc.
The amount of energy use in institutional/office buildings depends on the building envelope, operational efficiency of the HVAC system, fresh air requirement, lighting system and their efficiency, internal plug loads, building operation and maintenance. The first category is the base load, which can be defined as the non-weather dependent energy use. The other category is energy use in the air conditioning plants and systems. This requires the determination of how much energy is used for heating and cooling, through energy use associated with fans and pumps. The aim of this project is to exercise your theoretical thermo-fluid knowledge and skills in a practical application in building HVAC systems.
You are required to study, analyze and assess two suitable air-conditioning systems of the building located in sub-tropical climate which will offer improved thermal comfortability of the people. Relevant technical data and other information on the existing building will be available on Moodle. Note that any information that is not given is at the HVAC Engineers’s discretion. Energy consumption profile and thermal comfort profile should be simulated using available Building Energy Performance Simulation Software, DesignBuilder. Students are required to develop a correlation with the thermal comfort and energy consumption profile for the given case and suggest the optimum level that meet the thermal comfortability index. The software is available to download at www.designbuilder.co.uk and you can download a trial version free of charge. The trial version of the software is functional for four weeks only. You/ your team will receive the student license from the teaching team later in the term. The software is also accessible in the computer labs for the Engineering students.
Your project outcomes should be presented in a technical report and the presentation. A team project report and a soft copy of the simulation results (DesignBuilder.dsb file).
1. Report submission for assessment should have at least the following items:
• Introduction (background information, aims, objectives, scopes & limitations etc.).
• Literature review on latest HVAC systems and their application to different types of buildings and industries
• Working principle of existing and proposed HVAC systems in the reference study building.
• Thermal comfort conditions, according to local climatic or weather data.
• Model development, system definition and classification of whole building into different thermal zones for HVAC control purposes.
• Compare results between single-zone and multi-zone model in the confined space.
• Simulation of energy consumption and indoor thermal environmental profile of the reference building with two suitable HVAC system for sub-tropical climate
• Evaluation of alternative HVAC systems alone with other ECMs in the simulation environment and develop a correlation with the thermal comfort and energy consumption profile for the given case and suggest the optimum level that meet the thermal comfortability index
• CFD analysis of temperature distribution in the reference building demonstrating that the comfort standard is achieved.
2. Project Presentation: Formal presentation of the Team project (10 minutes max) - highlighting the findings from the project will happen a week prior to the final submission. All member of the teams are required to meet the formal dress code and contribute significantly during the presentation.